Hi Yigit, thanks for getting back to me.
I tried again and when I click on the advanced layout button on another blank page it didn’t work again.
Then I thought if the account I setup for you works, maybe it was because of a user setting I had made. Turns out the ‘turn visual editor’ off causes the issue!
Have now turned that off for my user account and it seems to work fine now!
Got to the bottom of it anyway, thanks for your help ;)